An acidic environment in the mouth, whether from acids released by cariogenic bacteria or acids from nonbacterial sources, for example, acidic foods and drinks, exposure to chlorinated swimming pool water, and regurgitation of gastric acids, can lead to demineralization and damage to the tooth structure. Dentinal hypersensitivity is acute, localized tooth pain in response to physical stimulation of the dentine surface as by thermal (hot or cold) osmotic, tactile combination of thermal, osmotic and tactile stimulation of the exposed dentin. Exposure of the dentine, which is generally due to recession of the gums, or loss of enamel, frequently leads to hypersensitivity. Dentinal tubules open to the surface have a high correlation with dentine hypersensitivity, as exposed dentinal tubules provide a pathway for transmission of fluid flow to the pulpal nerves, the transmission induced by changes in temperature, pressure and ionic gradients.
Arginine has significant benefits in combating cavity formation and tooth sensitivity. Commercial arginine toothpaste formulations comprise arginine bicarbonate and calcium carbonate, which also acts as the abrasive system. Dentifrice formulations comprising arginine and calcium in combination with fluoride provide a significant enhanced anti-caries benefit compared to conventional dentifrices containing only fluoride, as documented in intra-oral caries clinical studies, 6 month caries clinical studies and a 2 year caries clinical study.
There remains an unmet need, however, for silica-based dentifrice formulations comprising arginine to promote remineralization of the teeth and enhanced anti-caries and anti-erosion benefits.